The invention relates to a multispindle-drilling machine for drilling series of holes, in particular in parts of pieces of furniture, and including a drilling head, feed means and driving means for drilling spindles, a positioning pin displaceable in the axial direction and fixable in upper and lower positions and mounted laterally with respect to the drilling head.
Multispindle-drilling machines of the afore-mentioned kind are used in furniture production for drilling series of holes. The standard distance between the individual holes of such series of drilled holes is 32 mm. Drilling machines are known by means of which a complete series of holes can be drilled into a piece of furniture in one operating step. Often the number of drilling spindles of the drilling head is smaller than the number of holes to be drilled into a furniture part, and the distance between the marking points for the holes to be drilled is such that the drilling head must be displaced with respect to the furniture part so that the drilling operation for finishing the desired series of holes can be repeated.
It is essential that the distances between the holes formed by one drilling operation and the holes are formed by the next drilling operation be 32 mm or a precise multiple thereof.
In a known multispindle-drilling machine a postioning pin disposed at a distance of 32 mm from the next drill and aligned in a line with the drills is arranged at each end of the drilling head. In its lower position the positioning pin extends beyond the drills.
Depending on whether the work-piece is moved to the right or to the left, the left or the right positioning pin can be locked in an upper position in which its lower end is higher than the points of the drills.
In this machine the positioning pin in operation and engaging the last hole of a previously drilled series of holes must be lifted from such last hole to enable the work-piece, e.g. a chipboard, to be moved for a subsequent drilling operation.